It is known that many pathologies of the lower limb, such as the pathology of the midfoot, backfoot, leg, knee and femure, can be improved by dampening the load exerted on the heel and the plantar arch of the foot during the deambulation or the run.
In fact, in patients suffering from limb relaxations, the weighing down of the body through the foot resting surface, when no cushioning means are provided, causes the subsidence of the plantar arch and the pronation of the heel. This implies the formation of a flat-pronated foot and, in turn, the generation of several troubles of both physiological and psychological character.
It is likewise known that the hip phrotesis anchored to the pelvis by means of cements, tend to be displaced by the progressive disintegration of the cements themselves because of the vibration transmitted by the lower limbs to the acetabulum during the deambulation.
Furthermore, in case of fractures of the heel, which--as everybody knows--is the bone that supports 75% of the body weight during the deambulation, serious problems arise for the laying down of the foot, which calls for long periods of rehabilitation before the patient is able to regain a normal deambulation capability.
Similarly, the formation of calcaneal prickles and, mostly, or needle-like ossifications which occur beneath the heel, is cause for violent painful reactions when the foot rests onto the groin. Finally, the fractures of the leg and those of the femure, frequently take far more time to consolidate than usual, so that the impact of the foot onto the ground must take place only to a limited degree, or not taking place altogether, to avoid the occurrence of fractures.
In case of the above-mentioned fractures, the physiological repair process is strongly impaired, by the sudden impact of the foot onto the ground, also and, above all, by the vibrations transmitted to the whole lower limb upon the impact.
Also the arthrosis of the hip, of the knee and of the ankle, are subject to a progressive worsening if the foot is made to rest on the ground in the usual way, that is, without dampening the impact.
U.S. Pat. No. 4,928,404 discloses a calcaneum pad made of silicone rubber for insertion within a traditional shoe in correspondence of the heel below the wearer's calcaneum.
However, the disadvantages deriving from the above known heel paid consist essentially in that the only part which receives the cushioning action is the calcaneum and, accordingly, no action is exerted on the plantar arch to allow the message or the remodelling thereof. This is usually required in the rehabilitation process of the lower limbs in the majority of the previously mentioned pathologies.
Shoes are also known that are provided with elastic elements having linear elasticity, such as steel springs, fitted inside the heel to make it elastic.
However, the disadvantages deriving from these known shoes provided with springs fitted in the heel, lie essentially in the fact that during the relief phase, that is, when the foot is lifted from the ground, the springs give back all the elastic energy accumulated upon the weighing down phase, which is when the foot is made to rest on the ground. In this way the reaction exerted by the ground on the supporting foot is not dampened and is instead retransmitted unchanged onto the supporting lower limb. Also with these shoes, all the weight weighs down, during the deambulation, upon the calcaneum, which makes these type of shoes unsuitable for the massage and/or the remodelling of the plantar arch.